Add optionality for parameters

This commit allows for parameters that does not require any arguments to
be provided in function calls. It changes collection syntax where
parameters are list of objects instead of primitive strings. A
parameter has now 'name' and 'optional' properties. 'name' is required
and used in same way as older strings as parameter definitions.
'Optional' property is optional, 'false' is the default behavior if
undefined. It also adds additional validation to restrict parameter
names to alphanumeric strings to have a clear syntax in expressions.

src/application/Parser/Script/Compiler/Expressions/Expression/Expression.ts

@@ -1,12 +1,16 @@
 import { ExpressionPosition } from './ExpressionPosition';
-import { ExpressionArguments, IExpression } from './IExpression';
+import { IExpression } from './IExpression';
+import { IReadOnlyFunctionCallArgumentCollection } from '../../FunctionCall/Argument/IFunctionCallArgumentCollection';
+import { IReadOnlyFunctionParameterCollection } from '../../Function/Parameter/IFunctionParameterCollection';
+import { FunctionParameterCollection } from '@/application/Parser/Script/Compiler/Function/Parameter/FunctionParameterCollection';
+import { FunctionCallArgumentCollection } from '../../FunctionCall/Argument/FunctionCallArgumentCollection';
 
-export type ExpressionEvaluator = (args?: ExpressionArguments) => string;
+export type ExpressionEvaluator = (args: IReadOnlyFunctionCallArgumentCollection) => string;
 export class Expression implements IExpression {
     constructor(
         public readonly position: ExpressionPosition,
         public readonly evaluator: ExpressionEvaluator,
-        public readonly parameters: readonly string[] = new Array<string>()) {
+        public readonly parameters: IReadOnlyFunctionParameterCollection = new FunctionParameterCollection()) {
         if (!position) {
             throw new Error('undefined position');
         }
@@ -14,22 +18,42 @@ export class Expression implements IExpression {
             throw new Error('undefined evaluator');
         }
     }
-    public evaluate(args?: ExpressionArguments): string {
+    public evaluate(args: IReadOnlyFunctionCallArgumentCollection): string {
+        if (!args) {
+            throw new Error('undefined args, send empty collection instead');
+        }
+        validateThatAllRequiredParametersAreSatisfied(this.parameters, args);
         args = filterUnusedArguments(this.parameters, args);
         return this.evaluator(args);
     }
 }
 
-function filterUnusedArguments(
-    parameters: readonly string[], args: ExpressionArguments): ExpressionArguments {
-    let result: ExpressionArguments = {};
-    for (const parameter of Object.keys(args)) {
-        if (parameters.includes(parameter)) {
-            result = {
-                ...result,
-                [parameter]: args[parameter],
-            };
-        }
+function validateThatAllRequiredParametersAreSatisfied(
+    parameters: IReadOnlyFunctionParameterCollection,
+    args: IReadOnlyFunctionCallArgumentCollection,
+) {
+    const requiredParameterNames = parameters
+        .all
+        .filter((parameter) => !parameter.isOptional)
+        .map((parameter) => parameter.name);
+    const missingParameterNames = requiredParameterNames
+        .filter((parameterName) => !args.hasArgument(parameterName));
+    if (missingParameterNames.length) {
+        throw new Error(
+            `argument values are provided for required parameters: "${missingParameterNames.join('", "')}"`);
     }
-    return result;
+}
+
+function filterUnusedArguments(
+    parameters: IReadOnlyFunctionParameterCollection,
+    allFunctionArgs: IReadOnlyFunctionCallArgumentCollection): IReadOnlyFunctionCallArgumentCollection {
+    const specificCallArgs = new FunctionCallArgumentCollection();
+    for (const parameter of parameters.all) {
+        if (parameter.isOptional && !allFunctionArgs.hasArgument(parameter.name)) {
+            continue; // Optional parameter is not necessarily provided
+        }
+        const arg = allFunctionArgs.getArgument(parameter.name);
+        specificCallArgs.addArgument(arg);
+    }
+    return specificCallArgs;
 }